Commonly, angles of a headrest of a sofa can be adjusted to meet the requirement of the customers. One of the achievement manners is to set a hinge connected between a sofa body and the headrest in the sofa. As shown in FIG. 1, one end of the hinge a is installed to the sofa body b, the other end of the hinge a is installed to the headrest c, as the hinge a has a pivot joint, the headrest c is capable of swinging relative to the sofa body b so as to change the angle thereof. Combined with FIG. 2, the hinge a is mounted to the sofa body b via a metal sleeve d. A top plate b1 is fixed on an upper end of the sofa body b, has a thread is configured on the peripheral wall of the sleeve d and screwed up in the top plate b1, and then inserting a lower end of the hinge a so as to complete the installation.
The conventional sleeve for installing hinge has the following disadvantages: the sleeve need to be screwed in the top plate, which is time-consuming, and it is difficult to remove the sleeve once it is screwed therein; as the sleeve is configured with the thread, so the material of the sleeve must be metal, which increases the manufacturing costs.
Therefore, it is necessary to provide a sleeve for installing hinge having quick and easy installation, and low cost.